Milestones: 1784–1800

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Treaty of San Lorenzo/ Pinckney’s Treaty, 1795

Spanish and U.S. negotiators concluded the Treaty of San Lorenzo, also known as
Pinckney’s Treaty, on October 27, 1795. The treaty was an important diplomatic
success for the United States. It resolved territorial disputes between the two
countries and granted American ships the right to free navigation of the
Mississippi River as well as duty-free transport through the port of New
Orleans, then under Spanish control.

Thomas Pinckney

Prior to the treaty, the western and southern borders of the United States had
been a source of tension between Spain and the United States. The U.S. border
extended to the Mississippi River, but its southern stretch remained in Spanish
territory, and Spanish officials, reluctant to encourage U.S. trade and
settlement in a strategic frontier area, kept the Mississippi River closed to
American shipping. Moreover, both Spain and the United States claimed portions
of the present-day states of Alabama and Mississippi, and earlier negotiations
to resolve the territorial disputes had broken off inconclusively. The Spanish
government maintained several forts in the disputed territories, and could also
count on indigenous resistance to U.S. attempts to survey or encroach upon
Native American lands. U.S. citizens from the southern states and frontier areas
found Spanish policies restrictive, and wanted the U.S. Government to
renegotiate its positions.

Prior to 1789, Spanish policy had focused on keeping American trade and
settlement in frontier areas to a minimum, and so neither Spanish colonial
officials nor policymakers in Madrid were interested in granting the concessions
that U.S. negotiators had attempted to obtain earlier. However, Spanish
interests changed during the wars of the French Revolution. Spain joined the
other European monarchies in war against France in 1793, but by 1794 Spanish
forces experienced defeats in the Caribbean and Europe. Spanish King Charles IV,
uninterested in managing political affairs, had earlier handed political and
diplomatic responsibilities to his prime minister, Manuel de Godoy. Godoy sought
to extract Spain from its alliance with its traditional enemy Great Britain, and
to restore peace with France. Godoy’s policy was not without risks, as
antagonizing the British would put Spanish colonies in the Americas at risk.

While Spanish diplomats sought to shift Spanish alliances, U.S. diplomat John Jay
arrived in London to negotiate a treaty with Great Britain. Spanish officials
feared that Jay’s negotiations would result in an Anglo-American alliance and an
invasion of Spanish possessions in North America. Sensing the need for
rapprochement, Godoy sent a request to the U.S. Government for a representative
empowered to negotiate a new treaty. President George
Washington selected South Carolinian Thomas
Pinckney, who had been serving as United States minister to Great
Britain.

Charles IV of Spain

Pinckney arrived in Spain in June of 1795, and negotiations proceeded swiftly.
Spain’s political and military position had weakened under its defeats and war
expenses, while population growth in Kentucky and Tennessee, combined with a
shortage of European ships to sustain trade with Louisiana, made Spanish
officials amenable to a change in restrictive Spanish trade policies. Godoy
offered to accept the 31st parallel as the U.S.-Florida border as well as the
right to free navigation of the Mississippi, which Americans west of the
Appalachians supported enthusiastically. In return, Godoy requested that the
United States commit to an alliance with Spain.

Pinckney rejected the alliance, and after further consultation Godoy provided the
same offer without the necessity of the alliance. Nevertheless, negotiations
came to an impasse as the Spanish continued to insist on their right to require
duties for goods passing through Spanish-held New Orleans. Pinckney threatened
to leave without signing a treaty unless the Spanish dropped duties on American
trade passing through New Orleans. The next day, Godoy agreed to Pinckney’s
demands, and the two negotiators signed the treaty on October 27, 1795. The
final treaty also voided Spanish guarantees of military support that colonial
officials had made to Native Americans in the disputed regions, greatly
weakening those communities’ ability to resist encroachment upon their
lands.

The Treaty of San Lorenzo enabled and encouraged American settlers to continue
westward expansion, and made frontier areas more attractive and lucrative.
Consequently, it was popular with the American public, especially in the West
and South. Since Thomas Pinckney was associated with the Federalist Party, the
treaty served to bolster the Federalists outside of their New England stronghold
and give the party a stronger base in areas where it had traditionally been
weak. Diplomatically, the treaty marked a reverse in Spanish policies that
attempted to maintain a strong buffer region in North America, while placing the
United States in a stronger position in relation to European powers compared to
the U.S. concessions made in Jay’s Treaty.